1. Field of the Invention
This invention pertains to swinging doors and gates, and more particularly to apparatus that enables doors and gates to swing freely in one direction but to be controlled when swinging in the other direction.
2. Description of the Prior Art
Modern agricultural equipment includes heavy duty trucks and trailers with large boxes for hauling harvested grain, forage, and other products. An exemplary agricultural box is manufactured by Meyer Manufacturing Corporation of Dorchester, Wis. The box has a floor mounted on the truck or trailer chassis, and front and side walls that upstand from the floor. The back of the box is closeable by a gate that swings about a horizontal axis at the top of the gate. The gate is normally vertical and is latched closed.
To unload the material in the box, apron chains are frequently used. In some boxes, actuating the apron chains automatically unlatches the gate. The apron chains move rearwardly along the box floor and propel the material out the back end of the box. The force of the moving material is sufficient to swing the gate open and propel the material under it. When all the material has been unloaded, the gate swings closed by gravity to its normal closed vertical position.
A problem with prior gates was that, because of their weight, they tended to swing closed before all the material had been discharged from the box. Consequently, the last quantity of material moved only slowly out of the box under the mostly closed gate. The delay in completely unloading the box was detrimental to high farm productivity.
Thus, a need exists for improvements in unloading material from agricultural boxes.